Here is a drawing depicting the layout of thick and thin sided cases,
like my 585/375/416 HE thin sided ones and the thick one in picture.

And my 585 case is not perfect, as where it transitions from the
heavier corner to the side it isn't gradual, so case separates there
shortening case life. There are others made that way including brand X.
The dotted line is what it should be............

Others have sent cases to section and look at, that are built thick sided and they
stick also for the folks, If a longer case with about 5 sq in of side surface sticks and
don't spring back, the coefficient of friction is about .01 then the pull needed to move
it is 2500-3500 lbs..That is for big cases with normal amount of slant to the sides.

Here is picture of six nyati and gibbs size cases sectioned.. the5th one is present 585 HE
and 6th is thick sided version. 1st 600 OK which essentially nyati basic case left straight, belt added

In the picture the nyati gma is one we built most of our first 585s on. Before we had factory run.
Reworking made it in size that is my 585 HE, but that brass had the sides of perfect thickness,
not too thick, but thin without sharp transition my new factory 585s had, they last forever as 585s......

Fourth one is an older nyati case I used to make about 10 of my 585s from,had thin sides, heavy corner
and sharp transition from the corner, tested 20 years ago, and they would separate after 4-6 hot loads
as 585s, my factory 585 with right powders, as a 585 will get 10 hot loads, and necked down to
416/375 4- 6 hot loads, right powders used, Moderate 577 equivalent, factory 585 at least 20 loads..Ed.

Guy sent thick sided 375 case, next size base diameter up from Nyati.He said,
'Yes I ran them in a ___________ rifle built by ____, the best I
could get was 44000 psi, any more and they were stuck''

Big bore guys. other forums over the years related that trex/african case in 585
size, thick sided cases, stuck when they loaded them over 45k psi.

Another just sent us, thick sided 375, long case, same base OD as our 585 HE,
416 HE, 375 HE, and Mitch's 375 Lethal, and the thick ones stuck over 45k psi.

Now you can fill those cases up, with ultra slow enough powder so they won't
stick, but powder is too slow for max speed. Might get a little more
speed, with thick sides case, but case got to be 4- 4.5 inches long..

. Anyone needing a sectioned case of the ones I made the first of my 585s from,
contact me, if they want to get a general idea of what case side thickness should
be, in Gibbs size cases on up to about trex and 375 VM size case diameter.

Here is pic of our 585 based case next to brand X and thick ones, both have
same sharp, thinner, corner, where transition from heavy angled corner, to the
side, the carbide draw rod could easily be reshaped with diamond wheel,
just by grinding off sharp transition corner. Then sides would be perfect.., .

Here is picture of 416 HE in a Choate target/varmint stock guy is doing,
using long action BSA U9 action.Setting in stock ready to do bedding..Ed

Here is picture of thick 375 case sent to me, with thick sided trex case, and our HE case,
The thick 375 case is .050" bigger OD base, but inside is no bigger than HE cases..
These thick sided 375s stuck for the guy using them, when loaded over 44,000 psi....

Got guys asking and doing it, to do 416 HSM case for BMG actions, so leaving rim same,
as the original bmg rim, so will neck them, fire form to the longer shoulder, like the others.
Base a little bigger, Shoulder same diameter, same 30 degree slant, neck will be same..

Inside of case still has close to same shape, volumne within 3 % as ones we slimmed down more.
Some want to use bmg actions and can't wait for intermediate actions, or already have bmg action.
And they are really getting interested in the complete line of 416 CEB bullets now being done
clear up to 550 gr...

So there will be 3 versions, one for actions .750" bolt, one for .800-.850" bolt,
And one for bigger bmg bolts. The ones for BMG called 416 HSM2 ..

Here is 416 HSM guy working in a Montana PH, in a heavy thumbhole target stock. Ed

The heaviest 550 gr for Extreme ELR probably be best 8 to 1 twist , in 416 caliber bullet,
and 520 gr 9.5 to 1, and 470gr 10 to one, Some barrels I picked up are 10 to 1.......

Now a novel idea is to lighten rear of bullet with small shallow hole drilled in base, might do better
long range.which would allow 10 to one barrel stabilize the heavier 550 gr bullets for ELR.
Making bullet nose heavier makes it more stable in flight, needing less spin,
like our hollow base 585 cal minie bullets only need 48 to 1 twist, or less
while out regular 585 bullets need about 24 to 1 to stabilise them..............

The winner of the King Of 2 Mile shoot last week was using 416 Barrett with a 1 to 10
twist, with a 500 gr CEB Lazer bullet, ...Robert Brantley, with Manners Stocks....

Paul Philips was third with a 416...

GOOD NEWS-- There is now an importer and seller of our 585 HE brass getting set up here,
in US, hopefully will be in stock, few weeks........ http://bertrambrass.com .. .. Caleb Hallet..

Have got another intermediate size action besides the Montana PH our guys working on,
to do speed testingwith. It is big long REM style action that can take our 416 HSM, ED